JPH05319815A - Preparation of calcium carbonate dispersion - Google Patents
Preparation of calcium carbonate dispersionInfo
- Publication number
- JPH05319815A JPH05319815A JP15598992A JP15598992A JPH05319815A JP H05319815 A JPH05319815 A JP H05319815A JP 15598992 A JP15598992 A JP 15598992A JP 15598992 A JP15598992 A JP 15598992A JP H05319815 A JPH05319815 A JP H05319815A
- Authority
- JP
- Japan
- Prior art keywords
- calcium carbonate
- aqueous suspension
- suspension
- value
- water
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F11/00—Compounds of calcium, strontium, or barium
- C01F11/18—Carbonates
- C01F11/185—After-treatment, e.g. grinding, purification, conversion of crystal morphology
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F11/00—Compounds of calcium, strontium, or barium
- C01F11/18—Carbonates
- C01F11/181—Preparation of calcium carbonate by carbonation of aqueous solutions and characterised by control of the carbonation conditions
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Inorganic Chemistry (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、二次凝集が少なく分散
性の良好な合成炭酸カルシウムの製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a synthetic calcium carbonate having a small amount of secondary aggregation and a good dispersibility.
【０００２】[0002]
【従来の技術】現在、合成炭酸カルシウムの工業的製造
方法としては、炭酸ガス法が広く採用されている。この
炭酸ガス法とは、天然に産する石灰石を焼成することに
より生石灰（酸化カルシウム）を得、この生石灰と水を
反応させ石灰乳（水酸化カルシウムの水懸濁液）を得、
この石灰乳に、石灰石を焼成する際に発生する炭酸ガス
を導通し反応させることにより炭酸カルシウムを得る方
法である。この炭酸ガス法により製造される合成炭酸カ
ルシウムは、その一次粒子の大きさに応じて、ゴム、プ
ラスチック、紙、塗料等の填料又は顔料として、広く大
量に使用されている。また、これらの用途に用いられる
合成炭酸カルシウムは、その配合時の物性をさらに向上
させるため、粒子表面にその使用目的に応じた無機系又
は有機系の様々な処理剤が表面処理され一般に使用され
ている。2. Description of the Related Art At present, the carbon dioxide method is widely used as an industrial method for producing synthetic calcium carbonate. With this carbon dioxide method, quicklime (calcium oxide) is obtained by firing naturally produced limestone, and this quicklime and water are reacted to obtain lime milk (aqueous suspension of calcium hydroxide),
In this method, calcium carbonate is obtained by allowing carbon dioxide gas generated when firing limestone to pass through and react with this lime milk. The synthetic calcium carbonate produced by the carbon dioxide method is widely used in large amounts as a filler or pigment for rubber, plastic, paper, paint, etc., depending on the size of the primary particles. In addition, synthetic calcium carbonate used for these purposes is generally used by surface-treating various inorganic or organic treatment agents according to the intended use of the particles in order to further improve the physical properties at the time of compounding. ing.
【０００３】しかし乍ら、この炭酸ガス法で製造される
合成炭酸カルシウムは、元来一次粒子間の凝集力が非常
に強いものであり、一次粒子が多数凝集して大きな二次
粒子（一次粒子の粗大凝集体）を形成しており、この二
次粒子のスラリーは、長時間強力に攪拌を続けても、ほ
ぼ一次粒子にまで分散させることは不可能であるとされ
ている。このような一次粒子の凝集体を多数含有する合
成炭酸カルシウムを、ゴム、プラスチック、紙、塗料等
の填料又は顔料として使用した場合、二次粒子があたか
も一次粒子のような挙動を示すため、分散不良、強度の
低下、光沢の低下、流動性の悪化等、良好な物性が得ら
れず、本来一次粒子を配合した場合の様な配合効果が得
られない。また同様に、このように多数の凝集体を含有
する合成炭酸カルシウムに、無機系又は有機系の表面処
理剤を処理しても二次粒子表面のみが処理されるにすぎ
ず、充分な効果を発揮するに至らない。However, the synthetic calcium carbonate produced by the carbon dioxide method originally has a very strong cohesive force between primary particles, and a large number of primary particles aggregate to form large secondary particles (primary particles). It is said that it is impossible to disperse the slurry of the secondary particles into almost the primary particles even if the slurry is strongly stirred for a long time. When synthetic calcium carbonate containing a large number of aggregates of such primary particles is used as a filler or pigment for rubber, plastic, paper, paints, etc., the secondary particles behave as if they were primary particles, and therefore are dispersed. Poor physical properties such as poor strength, low strength, low gloss, and poor fluidity cannot be obtained, and the same effect as originally obtained by mixing primary particles cannot be obtained. Similarly, even if the synthetic calcium carbonate containing a large number of aggregates is treated with an inorganic or organic surface treatment agent, only the secondary particle surface is treated, and a sufficient effect is obtained. It does not come to the full.
【０００４】現在まで、これら一次粒子凝集体を分散さ
せる方法は幾多報告されているが、一般にボールミル、
サンドグラインダーミル等により、強力に粉砕破壊する
方法が採用されている。しかし乍ら、このような方法は
強大なエネルギーを使用した摩砕粉砕であるため、経済
的に不利であるばかりではなく、炭酸カルシウムの凝集
体の分散が行なわれると同時に一次粒子の破壊も行なわ
れ、その結果表面状態の非常に不安定な、しかも希望す
る一次粒子径よりさらに小さな粒子と、分散が不完全な
二次凝集粒子とが混在し、粒度の分布が幅広くなってし
まうため、好ましい方法であるといいがたい。またこの
ようなサンドグラインダー等の湿式粉砕機には、通常粉
砕用メディアとして微少なガラスビーズが用いられる
が、炭酸カルシウムの粉砕破壊工程時これらガラスビー
ズ表面も粉砕破壊されるため、分散処理後の炭酸カルシ
ウム中に２０μｍ前後の粗大ガラス片が多数混入するこ
とになり、例えば１５μｍ前後の厚みの薄物フィルムの
充填剤として使用するような炭酸カルシウムをこのよう
な湿式粉砕方法を用いて分散調製することは好ましくな
い。Until now, many methods for dispersing these primary particle agglomerates have been reported. Generally, ball mills,
The method of crushing and destroying with a sand grinder mill is adopted. However, such a method is not only economically disadvantageous because it is a grinding and pulverization using a large amount of energy, but also the aggregates of calcium carbonate are dispersed and the primary particles are destroyed at the same time. As a result, the surface state is very unstable, and particles having a particle size smaller than the desired primary particle size and secondary agglomerated particles with incomplete dispersion are mixed, and the particle size distribution becomes wide, which is preferable. I hope it is a method. Further, in such a wet grinder such as a sand grinder, fine glass beads are usually used as a grinding medium, but the surface of these glass beads is also ground and broken during the grinding and breaking step of calcium carbonate. A large number of coarse glass pieces of about 20 μm are mixed in calcium carbonate. For example, calcium carbonate used as a filler for a thin film having a thickness of about 15 μm is dispersed and prepared by such a wet pulverization method. Is not preferable.
【０００５】また特開昭５９−６９４２５には、炭酸ガ
ス法により炭酸カルシウムを調製する炭酸化工程におい
て、ストロンチウム塩又はバリウム塩を少量添加するこ
とによる、分散性良好な合成炭酸カルシウムの製造方法
が提案されている。この方法によれば、良好な分散性を
有する合成炭酸カルシウムは調製し得るものの、該方法
で得られる炭酸カルシウム中には、炭酸化工程で添加し
たストロンチウム塩又はバリウム塩が混在しており、こ
れらストロンチウム塩又はバリウム塩を経済的に有利な
条件で除去することが困難であるため、このような炭酸
カルシウムは例えば食品用途への利用はできず、炭酸カ
ルシウムの用途が限定されるため、好ましい分散方法と
は言えない。Further, JP-A-59-69425 discloses a method for producing synthetic calcium carbonate having good dispersibility by adding a small amount of strontium salt or barium salt in the carbonation step of preparing calcium carbonate by the carbon dioxide method. Proposed. According to this method, although a synthetic calcium carbonate having good dispersibility can be prepared, the calcium carbonate obtained by the method contains strontium salt or barium salt added in the carbonation step, Since it is difficult to remove the strontium salt or barium salt under economically advantageous conditions, such calcium carbonate cannot be used for, for example, food applications, and the use of calcium carbonate is limited, so that a preferable dispersion is obtained. Not a method.
【０００６】[0006]
【発明が解決しようとする課題】本発明は、従来の合成
炭酸カルシウムの分散方法の欠点を補い、且つ経済的に
有利に分散性の良好な炭酸カルシウムの調製方法を提供
するものである。DISCLOSURE OF THE INVENTION The present invention provides a method for preparing calcium carbonate which has the disadvantages of the conventional methods for dispersing synthetic calcium carbonate and which is economically advantageous and has good dispersibility.
【０００７】[0007]
【課題を解決するための手段】本発明者らは、上記課題
を解決するべく鋭意検討の結果、特定の条件下において
炭酸化反応して得られる炭酸カルシウムの水懸濁液を、
特定の条件、方法を用い、水懸濁液中に存在するアルカ
リ物質を除去及び／又はアルカリ物質の単位体積当たり
の濃度を低下せしめることにより、容易に分散性良好な
合成炭酸カルシウムが得られることを見いだし、本発明
を完成した。Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that an aqueous suspension of calcium carbonate obtained by a carbonation reaction under specific conditions is
A synthetic calcium carbonate having good dispersibility can be easily obtained by removing the alkaline substance existing in the water suspension and / or reducing the concentration of the alkaline substance per unit volume by using specific conditions and methods. Then, the present invention was completed.
【０００８】即ち、本発明は、石灰乳を炭酸ガスを用い
て炭酸化反応して得られる炭酸カルシウムの水懸濁液の
調製工程において、炭酸化反応終了して調製されたpH値
Ｘの炭酸カルシウムの水懸濁液を攪拌、及び／又は湿式
粉砕、及び／又は静置し、該炭酸カルシウムの水懸濁液
のpHを以下に示す式（ａ）及び（ｂ）を満たすpH値Ｙに
上昇せしめた後、水懸濁液中に存在するアルカリ物質を
除去及び／又はアルカリ物質の単位体積当たりの濃度を
低下せしめ、炭酸カルシウムの水懸濁液のpHを、以下に
示す式（ｃ）を満たすpH値Ｚに調整することを特徴とす
る、炭酸カルシウム分散体の製造方法を内容とするもの
である。 Ｙ≧８．６ ・・・（ａ） １０(Y+2) ／１０X ≧１２５ ・・・（ｂ） １０(Z+2) ／１０Y ≦８０ ・・・（ｃ） 但し、Ｘ、Ｙは同一温度条件下でのpHである。pH値Ｚ
は、Ｚが８．６未満の場合、Ｚは８．６として計算す
る。That is, according to the present invention, in the step of preparing an aqueous suspension of calcium carbonate obtained by the carbonation reaction of lime milk with carbon dioxide gas, the carbonic acid having a pH value X prepared after completion of the carbonation reaction is prepared. The aqueous suspension of calcium is stirred and / or wet-ground and / or allowed to stand, and the pH of the aqueous suspension of calcium carbonate is adjusted to a pH value Y satisfying the following formulas (a) and (b). After raising, the alkaline substance present in the aqueous suspension is removed and / or the concentration of the alkaline substance per unit volume is lowered, and the pH of the aqueous suspension of calcium carbonate is calculated by the formula (c) shown below. A method for producing a calcium carbonate dispersion, characterized in that the pH value Z satisfying the above conditions is adjusted. Y ≧ 8.6 (a) 10 (Y + 2) / 10 X ≧ 125 (b) 10 (Z + 2) / 10 Y ≦ 80 (c) where X and Y Is the pH under the same temperature conditions. pH value Z
Calculates Z as 8.6 if Z is less than 8.6.
【０００９】本発明において、石灰乳を炭酸ガスを用い
て炭酸化する方法に関しては特に制限はなく、石灰乳中
に炭酸ガスを導通する方法、炭酸ガス中に石灰乳を噴霧
する方法等、常法の方法によればよい。また、炭酸化反
応条件に関しても、所望の炭酸カルシウムの粒子径に応
じ、石灰乳濃度、石灰乳温度、炭酸ガス濃度、炭酸ガス
導通量、石灰乳噴霧速度、石灰乳噴霧液滴径等の反応条
件を任意に選択し炭酸化反応を開始すればよく、炭酸化
開始後炭酸化反応系内のpHが任意の時点で、好ましくは
１１．０以下に達した任意の時点で、より好ましくは１
０．０以下に達した任意の時点で炭酸化反応を終了すれ
ばよい。In the present invention, there is no particular limitation on the method of carbonating lime milk using carbon dioxide gas, such as a method of conducting carbon dioxide gas in lime milk, a method of spraying lime milk in carbon dioxide gas, etc. According to the method of law. Regarding the carbonation reaction conditions, the reaction such as lime milk concentration, lime milk temperature, carbon dioxide concentration, carbon dioxide gas conduction amount, lime milk spraying speed, lime milk spraying droplet diameter, etc. is performed according to the desired particle size of calcium carbonate. It suffices to arbitrarily select the conditions and start the carbonation reaction. After the start of carbonation, the pH in the carbonation reaction system is at any time, preferably at any time when it reaches 11.0 or less, more preferably 1
The carbonation reaction may be terminated at any time when it reaches 0.0 or less.
【００１０】次に、炭酸化反応終了後、得られる炭酸カ
ルシウムの水懸濁液を攪拌及び／又は静置し、炭酸カル
シウム粒子間に存在するアルカリ物質を溶出させ、該炭
酸カルシウムの水懸濁液のpHを上記（ａ）及び（ｂ）を
満たすpH値Ｙに上昇せしめればよく、好ましくはＸ及び
Ｙは下記（ｄ）（ｅ）、より好ましくは（ｆ）（ｇ）を
満たすpH値Ｙに上昇せしめればよい。 Ｙ≧１０．０ ・・・（ｄ） １０(Y+2) ／１０X ≧２００ ・・・（ｅ） Ｙ≧１０．５ ・・・（ｆ） １０(Y+2) ／１０X ≧２５０ ・・・（ｇ）After completion of the carbonation reaction, the obtained calcium carbonate aqueous suspension is stirred and / or allowed to stand to elute the alkaline substance existing between the calcium carbonate particles, and the calcium carbonate is suspended in water. It suffices to raise the pH of the liquid to a pH value Y satisfying the above (a) and (b), preferably X and Y satisfying the following (d) and (e), more preferably (f) and (g). The value Y should be raised. Y ≧ 10.0 ・ ・ ・ (d) 10 (Y + 2) / 10 X ≧ 200 ・ ・ ・ (e) Y ≧ 10.5 ・ ・ ・ (f) 10 (Y + 2) / 10 X ≧ 250 ... (g)
【００１１】攪拌及び／又は静置により、該炭酸カルシ
ウムの水懸濁液のpHが８．６未満の場合、アルカリ物質
除去等の本発明の方法を実施しても、分散性の良好な炭
酸カルシウムは得られないため、該水懸濁液を湿式粉砕
機を用いて解砕し、そのpHを８．６以上にすればよい。
また、１０(Y+2) ／１０X が１２５未満の場合、本発明
の以降の操作を行っても、本発明の目的である分散性良
好な炭酸カルシウムを得ることはできない。When the pH of the calcium carbonate aqueous suspension is less than 8.6 by stirring and / or standing, even if the method of the present invention such as removal of an alkaline substance is carried out, the carbonic acid with good dispersibility is obtained. Since calcium cannot be obtained, the aqueous suspension may be crushed using a wet crusher to adjust its pH to 8.6 or higher.
Further, when 10 (Y + 2) / 10 X is less than 125, it is not possible to obtain calcium carbonate having good dispersibility, which is the object of the present invention, even if the subsequent operations of the present invention are performed.
【００１２】次に、上記（ａ）及び（ｂ）を満たすpH値
Ｙに上昇させた炭酸カルシウムの水懸濁液中に存在する
アルカリ物質を除去及び／又はアルカリ物質の単位体積
当たりの濃度を低下せしめ、炭酸カルシウムの水懸濁液
のpHを、前述の（ｃ）を満たすpH値Ｚに調整すればよ
く、好ましくはpH値Ｚは下記（ｈ）、より好ましくは
（ｉ）を満たすpH値Ｚに調製することにより、本発明の
目的を達成することができる。pH値Ｚを８．６未満にす
る場合のみ、Ｚ＝８．６として計算した値を採用する。 １０(Z+2) ／１０Y ≦７０ ・・・（ｈ） １０(Z+2) ／１０Y ≦６０ ・・・（ｉ） １０(Z+2) ／１０Y が８０を越える場合、水懸濁液中に
存在するアルカリ物質を除去及び／又はアルカリ物質の
単位体積当たりの濃度を低下させることが充分ではな
く、本発明の目的である分散性良好な炭酸カルシウムを
得ることはできない。本発明における、炭酸カルシウム
の水懸濁液中に存在するアルカリ物質を除去及び／又は
アルカリ物質の単位体積当たりの濃度を低下させる方法
については、特別の制限は無く、アルカリ物質と反応し
水に不溶性又は難溶性の塩を生成する酸性ガスを水懸濁
液と反応させる方法、アルカリ物質と反応し水に不溶性
又は難溶性の塩を生成する燐酸、シュウ酸等を水懸濁液
に添加する方法、水で希釈又は洗浄する方法等いずれの
方法を採用してもよい。Next, the alkaline substance existing in the aqueous suspension of calcium carbonate having a pH value Y satisfying the above (a) and (b) is removed and / or the concentration of the alkaline substance per unit volume is adjusted. The pH value of the aqueous suspension of calcium carbonate may be lowered to a pH value Z satisfying the above-mentioned (c), preferably the pH value Z is the following (h), more preferably the pH satisfying the (i). By adjusting the value Z, the object of the present invention can be achieved. Only when the pH value Z is less than 8.6, the value calculated as Z = 8.6 is adopted. 10 (Z + 2) / 10 Y ≦ 70 ・ ・ ・ (h) 10 (Z + 2) / 10 Y ≦ 60 ・ ・ ・ (i) 10 (Z + 2) / 10 If Y exceeds 80, water It is not sufficient to remove the alkaline substance present in the suspension and / or reduce the concentration of the alkaline substance per unit volume, and it is not possible to obtain calcium carbonate having good dispersibility, which is the object of the present invention. In the present invention, there is no particular limitation on the method of removing the alkaline substance present in the aqueous suspension of calcium carbonate and / or reducing the concentration of the alkaline substance per unit volume, and it is reacted with the alkaline substance to form water. A method of reacting an acidic gas that forms an insoluble or sparingly soluble salt with an aqueous suspension, and adding phosphoric acid, oxalic acid, etc., which reacts with an alkaline substance to form an insoluble or sparingly soluble salt in water, to an aqueous suspension Any method such as a method and a method of diluting or washing with water may be adopted.
【００１３】特に食品用途、その他広範囲の工業用途に
広く用いるための炭酸カルシウムの調製には、炭酸カル
シウム以外の不純物が可能な限り少ないほうが好ましい
ため、炭酸カルシウムの水懸濁液中に存在するアルカリ
物質を除去及び／又はアルカリ物質の単位体積当たりの
濃度を低下させる好ましい方法としては、以下に示す
の方法を例示できる。これらの方法は、単独
で採用しても２以上組み合わせて採用しても問題なく、
これらの方法により炭酸カルシウムの水懸濁液のpH値Ｚ
を前述の（ｃ）を満たす値に調整することにより、本発
明の良好な分散性を有する一次粒子径が０．０１〜５μ
ｍの炭酸カルシウムを、容易にかつ経済的に有利に調製
することが可能となる。 pH値Ｙに上昇せしめた炭酸カルシウムの水懸濁液に、
炭酸ガス含有ガスを反応せしめ、炭酸カルシウムの水懸
濁液のpHをＺに調整する方法。 pH値Ｙに上昇せしめた炭酸カルシウムの水懸濁液に大
量の水を加え希釈し、炭酸カルシウムの水懸濁液のpHを
Ｚに調整する方法。 pH値Ｙに上昇せしめた炭酸カルシウムの水懸濁液を脱
水し、得られる含水ケーキ又は高濃度炭酸カルシウムの
水懸濁液に水を加えて希釈し、再度炭酸カルシウムの水
懸濁液を調製し、該水懸濁液のpHをＺに調整する方法。For the preparation of calcium carbonate for widespread use in food and other industrial applications, it is preferable that impurities other than calcium carbonate be as small as possible. As a preferable method for removing the substance and / or reducing the concentration of the alkaline substance per unit volume, the following methods can be exemplified. These methods can be used alone or in combination of two or more,
According to these methods, the pH value Z of an aqueous suspension of calcium carbonate
Is adjusted to a value satisfying the above (c), the primary particle diameter of the present invention having good dispersibility is 0.01 to 5 μm.
It is possible to easily and economically prepare the calcium carbonate of m. To an aqueous suspension of calcium carbonate whose pH value has been increased to Y,
A method of reacting a carbon dioxide-containing gas to adjust the pH of an aqueous suspension of calcium carbonate to Z. A method of adjusting the pH of an aqueous suspension of calcium carbonate to Z by adding a large amount of water to dilute the aqueous suspension of calcium carbonate which has been raised to a pH value Y. An aqueous suspension of calcium carbonate that has been raised to a pH value Y is dehydrated, and water is added to the obtained water-containing cake or an aqueous suspension of high-concentration calcium carbonate to dilute it to prepare an aqueous suspension of calcium carbonate again. And adjusting the pH of the aqueous suspension to Z.
【００１４】炭酸カルシウム粒子間に存在するアルカリ
物質の溶出に関する関数である１０(Y+2) ／１０X の計
算値については、採用した全方法の合計値から算出され
ればよい。仮に本発明の炭酸カルシウムの分散体を調製
するにあたり、上記の方法を２回、さらにの方法を
１回採用し、それぞれの１０(Y+2) ／１０X の計算値
が、の方法の１回目が５０、の方法の２回目が１０
０、の方法が１５０である場合、この方法の１０
(Y+2) ／１０X は、各々合計の３００とすればよい。ま
た、炭酸カルシウムの水懸濁液中に存在するアルカリ物
質を除去及び／又はアルカリ物質の単位体積当たりの濃
度を低下させる方法、例えば上記等の方法を単独
で複数回、又は組み合わせた方法で複数回行った場合の
１０(Z+2) ／１０Y の値は、各々単独の方法による値を
算出し、それら方法の最小値を採用する。仮に本発明の
炭酸カルシウムの分散体を調製するにあたり、上記の
方法を２回、の方法を１回、の方法を１回採用し、
それぞれの１０(Z+2) ／１０Y の計算値が、の方法の
１回目が１００、の方法の２回目が８０、の方法が
２０、の方法が６０である場合、この方法の１０
(Y+2) ／１０X は、の方法の数値の２０とすればよ
い。The calculated value of 10 (Y + 2) / 10 X , which is a function relating to the elution of the alkaline substance existing between the calcium carbonate particles, may be calculated from the total value of all the methods adopted. For the preparation of the calcium carbonate dispersion of the present invention, the above method is adopted twice and the further method is adopted once, and the calculated value of 10 (Y + 2) / 10 X is 1 Second time is 50, second time is 10
If the method of 0 is 150, then 10 of this method
(Y + 2) / 10 X may be 300 in total. Further, a method of removing an alkaline substance present in an aqueous suspension of calcium carbonate and / or reducing the concentration of the alkaline substance per unit volume, for example, the above-mentioned methods alone or a plurality of times, or a plurality of combined methods. As for the value of 10 (Z + 2) / 10 Y when repeated , the value is calculated by each independent method and the minimum value of those methods is adopted. To prepare the calcium carbonate dispersion of the present invention, the above method is used twice, the method is used once, and the method is used once.
If each calculated value of 10 (Z + 2) / 10 Y is 100 in the first method, 80 in the second method, 20 in the second method, 60 in the second method.
(Y + 2) / 10 X may be 20 which is the numerical value of the method.
【００１５】以上のような本発明の方法により調製され
る炭酸カルシウムは、脱水乾燥して粉体化しても従来の
炭酸カルシウム粉体と比較し極めて良好な分散性を有し
ているため、カルボン酸又はその塩、界面活性剤等の各
種表面処理剤で表面処理した本発明の方法による炭酸カ
ルシウム粉体は、塗料、インキ、製紙、シーラント、合
成樹脂、ゴム等の各種工業用用途に、顔料、填料として
広く利用することができ、また表面処理を施さない粉体
は、牛乳用カルシウム強化剤等の各種食品添加物等の用
途に広範囲に応用することが可能である。The calcium carbonate prepared by the method of the present invention as described above has extremely good dispersibility as compared with the conventional calcium carbonate powder even when dehydrated and dried to be powdered. The calcium carbonate powder by the method of the present invention, which has been surface-treated with various surface-treating agents such as acids or salts thereof and surfactants, is used as a pigment in various industrial applications such as paints, inks, papermaking, sealants, synthetic resins and rubbers. The powder which can be widely used as a filler and which is not subjected to surface treatment can be widely applied to various food additives such as calcium enhancer for milk.
【００１６】[0016]
【実施例】以下に実施例、比較例を示し本発明をより詳
細に説明するが、本発明はこれら実施例のみに限定され
るものではない。 実施例１ 比重１．０５５で温度が８℃の石灰乳７０００リッター
に、炭酸ガス濃度２７重量％の炉ガス（以下炭酸ガスと
略記する）を２４m3の流速で導通し炭酸化反応を行い、
２５℃におけるpHがpH９．５（Ｘ）の炭酸カルシウムの
水懸濁液を得た。この炭酸カルシウムは、電子顕微鏡で
観察した結果、一次粒子径が０．０５μｍの炭酸カルシ
ウムであった。その後３０℃で５時間攪拌し、炭酸カル
シウム水懸濁液の２５℃におけるpHが１１．８（Ｙ−
１）に達した時点でフィルタープレスを用いて脱水し、
炭酸カルシウム固形分濃度が４８重量％の脱水ケーキを
得た。次に得られた脱水ケーキに再度水を加え攪拌し、
脱水前の炭酸カルシウム水懸濁液と同一濃度の炭酸カル
シウム水懸濁液を得た。該炭酸カルシウムの水懸濁液の
pHは１１．５（Ｚ−１、Ｙ−２）であった。この炭酸カ
ルシウム水懸濁液に再度炭酸ガスを導通し、炭酸カルシ
ウム水懸濁液のpHを７．０（Ｚ−２）に低下せしめた。
本実施例で得られた水懸濁液中の炭酸カルシウムの遠心
沈降式粒度分布測定機ＳＡ−ＣＰ３（島津製作所製）に
よる粒度分布測定結果を表１に示す。粒度分布の測定結
果から、本実施例で得られた水懸濁液中の炭酸カルシウ
ムは、極めて良好な分散性を有していることが確認され
る。EXAMPLES The present invention will be described in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. Example 1 7,000 liters of lime milk having a specific gravity of 1.055 and a temperature of 8 ° C. was passed through a furnace gas (hereinafter abbreviated as carbon dioxide gas) having a carbon dioxide gas concentration of 27% by weight at a flow rate of 24 m 3 to carry out a carbonation reaction,
An aqueous suspension of calcium carbonate having a pH at 25 ° C of pH 9.5 (X) was obtained. As a result of observing with an electron microscope, this calcium carbonate was calcium carbonate having a primary particle diameter of 0.05 μm. After that, the mixture was stirred at 30 ° C for 5 hours, and the pH of the calcium carbonate aqueous suspension at 25 ° C was 11.8 (Y-.
When it reaches 1), it is dehydrated using a filter press,
A dehydrated cake having a calcium carbonate solid content concentration of 48% by weight was obtained. Next, water is added again to the obtained dehydrated cake and stirred,
An aqueous calcium carbonate suspension having the same concentration as that of the aqueous calcium carbonate suspension before dehydration was obtained. Of the aqueous suspension of calcium carbonate
The pH was 11.5 (Z-1, Y-2). Carbon dioxide gas was passed through the calcium carbonate aqueous suspension again to lower the pH of the calcium carbonate aqueous suspension to 7.0 (Z-2).
Table 1 shows the results of particle size distribution measurement of calcium carbonate in the water suspension obtained in this example by a centrifugal sedimentation type particle size distribution analyzer SA-CP3 (manufactured by Shimadzu Corporation). From the measurement result of the particle size distribution, it is confirmed that the calcium carbonate in the water suspension obtained in this example has extremely good dispersibility.
【００１７】実施例２ 実施例１のpH９．５（Ｘ−１）の炭酸カルシウム水懸濁
液を、５０℃で２４時間攪拌し、系内の２５℃における
pHが１１．７（Ｙ−１）であることを確認後、該炭酸カ
ルシウム水懸濁液に再度炭酸ガスを導通し、系内の２５
℃におけるpHを１０．０（Ｚ−１、Ｘ−２）に調製し
た。その後該炭酸カルシウム水懸濁液を５０℃で１０時
間攪拌し、水懸濁液のpHを１１．２（Ｙ−２）に調整
後、再度炭酸ガスを導通し、系内の２５℃におけるpHを
７．０（Ｚ−２）に低下せしめた。本実施例で得られた
水懸濁液中の炭酸カルシウムの粒度分布測定結果を表１
に示す。粒度分布の測定結果から、本実施例で得られた
水懸濁液中の炭酸カルシウムは、極めて良好な分散性を
有していることが確認される。Example 2 An aqueous calcium carbonate suspension having a pH of 9.5 (X-1) obtained in Example 1 was stirred at 50 ° C. for 24 hours, and the system was kept at 25 ° C.
After confirming that the pH was 11.7 (Y-1), carbon dioxide gas was passed through the calcium carbonate aqueous suspension again to remove 25
The pH at the temperature was adjusted to 10.0 (Z-1, X-2). Thereafter, the calcium carbonate aqueous suspension is stirred at 50 ° C. for 10 hours, the pH of the aqueous suspension is adjusted to 11.2 (Y-2), carbon dioxide gas is supplied again, and the pH at 25 ° C. in the system is adjusted. Was lowered to 7.0 (Z-2). Table 1 shows the measurement results of particle size distribution of calcium carbonate in the water suspension obtained in this example.
Shown in. From the measurement result of the particle size distribution, it is confirmed that the calcium carbonate in the water suspension obtained in this example has extremely good dispersibility.
【００１８】実施例３ 実施例１と同様の方法で炭酸化反応を行い調製した、pH
１０．７（Ｘ）の炭酸カルシウム水懸濁液を、１２時間
放置し、系内の２５℃におけるpHが１１．７（Ｙ）であ
ることを確認後、該炭酸カルシウム水懸濁液中に、該水
懸濁液の容積の４倍の水を添加し希釈した。その後該希
釈水懸濁液を２５℃で攪拌したところ、２５℃における
pHを１１．１（Ｚ）であった。本実施例で得られた水懸
濁液中の炭酸カルシウムの粒度分布測定結果を表１に示
す。粒度分布の測定結果から、本実施例で得られた水懸
濁液中の炭酸カルシウムは、極めて良好な分散性を有し
ていることが確認される。Example 3 The pH was adjusted by the carbonation reaction in the same manner as in Example 1, pH.
A 10.7 (X) calcium carbonate aqueous suspension was allowed to stand for 12 hours, and after confirming that the pH at 25 ° C. in the system was 11.7 (Y), the calcium carbonate aqueous suspension was added to the calcium carbonate aqueous suspension. , 4 times the volume of the water suspension was added for dilution. Then, the diluted water suspension was stirred at 25 ° C.
The pH was 11.1 (Z). Table 1 shows the results of measuring the particle size distribution of calcium carbonate in the aqueous suspension obtained in this example. From the measurement result of the particle size distribution, it is confirmed that the calcium carbonate in the water suspension obtained in this example has extremely good dispersibility.
【００１９】実施例４ 比重１．０９５で温度が２８℃の石灰乳７０００リッタ
ーに、炭酸ガスを１０m3の流速で導通し炭酸化反応を行
い、pH９．５（Ｘ）の炭酸カルシウムの水懸濁液を得
た。この炭酸カルシウムは、電子顕微鏡で観察した結
果、一次粒子径が１．５μｍの炭酸カルシウムであっ
た。その後３０℃で５時間攪拌し、炭酸カルシウム水懸
濁液の２５℃におけるpHが１１．８（Ｙ−１）に達した
時点でオリーバーフィルターを用いて脱水し、炭酸カル
シウム固形分濃度が４５重量％の脱水ケーキを得た。次
に得られた脱水ケーキに再度水を加え攪拌し、脱水前の
炭酸カルシウム水懸濁液の固形分濃度の半分の固形分濃
度の炭酸カルシウム水懸濁液を得た。該炭酸カルシウム
の水懸濁液のpHは１１．２（Ｚ−１、Ｙ−２）であっ
た。この炭酸カルシウム水懸濁液を再度フィルタープレ
スを用いて再度脱水し、再度炭酸カルシウム固形分濃度
が５０重量％の脱水ケーキを得た。次に得られた脱水ケ
ーキに再度水を加え攪拌し、脱水前の炭酸カルシウムと
同一濃度の炭酸カルシウム水懸濁液を得た。該炭酸カル
シウム水懸濁液のpHは１０．４（Ｚ−２）であった。本
実施例で得られた水懸濁液中の炭酸カルシウムの粒度分
布測定結果を表１に示す。粒度分布の測定結果から、本
実施例で得られた水懸濁液中の炭酸カルシウムは、極め
て良好な分散性を有していることが確認される。Example 4 Carbon dioxide gas was passed through 7,000 liters of lime milk having a specific gravity of 1.095 and a temperature of 28 ° C. at a flow rate of 10 m 3 to carry out a carbonation reaction, and water suspension of calcium carbonate of pH 9.5 (X) was carried out. A suspension was obtained. As a result of observation with an electron microscope, this calcium carbonate was found to have a primary particle diameter of 1.5 μm. After that, the mixture was stirred at 30 ° C. for 5 hours, and when the pH of the aqueous calcium carbonate suspension at 25 ° C. reached 11.8 (Y-1), dehydration was performed using an Oliver filter to obtain a calcium carbonate solid content concentration of 45. A weight percent dehydrated cake was obtained. Next, water was added again to the obtained dehydrated cake and the mixture was stirred to obtain a calcium carbonate aqueous suspension having a solid content concentration half that of the calcium carbonate aqueous suspension before dehydration. The pH of the calcium carbonate aqueous suspension was 11.2 (Z-1, Y-2). The calcium carbonate aqueous suspension was again dehydrated using a filter press to obtain again a dehydrated cake having a calcium carbonate solid content concentration of 50% by weight. Next, water was added again to the obtained dehydrated cake and the mixture was stirred to obtain a calcium carbonate aqueous suspension having the same concentration as that of calcium carbonate before dehydration. The pH of the calcium carbonate aqueous suspension was 10.4 (Z-2). Table 1 shows the results of measuring the particle size distribution of calcium carbonate in the aqueous suspension obtained in this example. From the measurement result of the particle size distribution, it is confirmed that the calcium carbonate in the water suspension obtained in this example has extremely good dispersibility.
【００２０】比較例１ 比重１．０５５で温度が８℃の石灰乳７０００リッター
に、炭酸ガスを２４m3の流速で導通し炭酸化反応を行
い、pH６．５（Ｘ）の炭酸カルシウムの水懸濁液を得
た。この炭酸カルシウムは、電子顕微鏡で観察した結
果、一次粒子径が０．０５μｍの炭酸カルシウムであっ
た。本比較例で得られた水懸濁液中の炭酸カルシウムの
粒度分布測定結果を表１に示す。粒度分布の測定結果か
ら、本比較例で得られた水懸濁液中の炭酸カルシウム
は、実施例１、２、３の炭酸カルシウムの分散性と比較
し、良好とは言えない分散性を有していることが確認さ
れる。Comparative Example 1 Carbon dioxide gas was passed through 7,000 liters of lime milk having a specific gravity of 1.055 and a temperature of 8 ° C. at a flow rate of 24 m 3 to carry out a carbonation reaction, and water suspension of calcium carbonate of pH 6.5 (X) was carried out. A suspension was obtained. As a result of observing with an electron microscope, this calcium carbonate was calcium carbonate having a primary particle diameter of 0.05 μm. Table 1 shows the results of particle size distribution measurement of calcium carbonate in the water suspension obtained in this comparative example. From the measurement results of the particle size distribution, the calcium carbonate in the water suspension obtained in this Comparative Example has a dispersibility which is not good as compared with the dispersibility of the calcium carbonates of Examples 1, 2 and 3. It is confirmed that it is doing.
【００２１】比較例２ 比重１．０９５で温度が２８℃の石灰乳７０００リッタ
ーに、炭酸ガスを１０m3の流速で導通し炭酸化反応を行
い、pH６．８（Ｘ）の炭酸カルシウムの水懸濁液を得
た。この炭酸カルシウムは、電子顕微鏡で観察した結
果、一次粒子径が１．５μｍの炭酸カルシウムであっ
た。本比較例で得られた水懸濁液中の炭酸カルシウムの
粒度分布測定結果を表２に示す。粒度分布の測定結果か
ら、本比較例で得られた水懸濁液中の炭酸カルシウム
は、実施例４の炭酸カルシウムの分散性と比較し、良好
とは言えない分散性を有していることが確認される。Comparative Example 2 Carbon dioxide gas was passed through 7,000 liters of lime milk having a specific gravity of 1.095 and a temperature of 28 ° C. at a flow rate of 10 m 3 to carry out a carbonation reaction, and water suspension of calcium carbonate of pH 6.8 (X) was carried out. A suspension was obtained. As a result of observation with an electron microscope, this calcium carbonate was found to have a primary particle diameter of 1.5 μm. Table 2 shows the particle size distribution measurement results of calcium carbonate in the water suspension obtained in this comparative example. From the measurement results of the particle size distribution, the calcium carbonate in the water suspension obtained in this Comparative Example has a dispersibility which is not good as compared with the dispersibility of the calcium carbonate in Example 4. Is confirmed.
【００２２】比較例３ 比重１．０５５で温度が８℃の石灰乳７０００リッター
に、炭酸ガスを２４m3の流速で６分間導通し炭酸化反応
を開始し、その後２m3の流速で炭酸化反応を継続し、pH
６．５（Ｘ）の炭酸カルシウムの水懸濁液を得た。この
炭酸カルシウムは、電子顕微鏡で観察した結果、一次粒
子径が０．０５μｍの炭酸カルシウムであった。この水
懸濁液を２５℃で維持し２４時間攪拌し、系内の２５℃
におけるpHが８．５（Ｙ）であることを確認後、該炭酸
カルシウム水懸濁液に再度炭酸ガスを導通し、系内の２
５℃におけるpHを７．０（Ｚ）に低下せしめた。本比較
例で得られた水懸濁液中の炭酸カルシウムの粒度分布測
定結果を表２に示す。粒度分布の測定結果から、本比較
例で得られた水懸濁液中の炭酸カルシウムは、実施例
１、２、３の炭酸カルシウムの分散性と比較し、良好と
は言えない分散性を有していることが確認される。Comparative Example 3 Carbon dioxide gas was introduced into 7,000 liters of lime milk having a specific gravity of 1.055 and a temperature of 8 ° C. at a flow rate of 24 m 3 for 6 minutes to start the carbonation reaction, and then the carbonation reaction was performed at a flow rate of 2 m 3. Continue at pH
An aqueous suspension of 6.5 (X) calcium carbonate was obtained. As a result of observing with an electron microscope, this calcium carbonate was calcium carbonate having a primary particle diameter of 0.05 μm. This water suspension is maintained at 25 ° C and stirred for 24 hours,
After confirming that the pH of the solution is 8.5 (Y), carbon dioxide gas is passed through the calcium carbonate aqueous suspension again, and
The pH at 5 ° C was lowered to 7.0 (Z). Table 2 shows the particle size distribution measurement results of calcium carbonate in the water suspension obtained in this comparative example. From the measurement results of the particle size distribution, the calcium carbonate in the water suspension obtained in this Comparative Example has a dispersibility which is not good as compared with the dispersibility of the calcium carbonates of Examples 1, 2 and 3. It is confirmed that it is doing.
【００２３】比較例４ 実施例１のpH９．５（Ｘ）の炭酸カルシウムの水懸濁液
を５分間放置し、系内の２５℃におけるpHが９．５５
（Ｙ）であることを確認後、該炭酸カルシウム水懸濁液
に再度炭酸ガスを導通し、系内の２５℃におけるpHを
６．５（Ｚ）に低下せしめた。本比較例で得られた水懸
濁液中の炭酸カルシウムの粒度分布測定結果を表２に示
す。粒度分布の測定結果から、本比較例で得られた水懸
濁液中の炭酸カルシウムは、実施例１、２、３の炭酸カ
ルシウムの分散性と比較し、良好とは言えない分散性を
有していることが確認される。Comparative Example 4 The aqueous suspension of calcium carbonate having a pH of 9.5 (X) of Example 1 was allowed to stand for 5 minutes, and the pH at 25 ° C. in the system was 9.55.
After confirming that it was (Y), carbon dioxide gas was passed through the calcium carbonate aqueous suspension again to lower the pH at 25 ° C. in the system to 6.5 (Z). Table 2 shows the particle size distribution measurement results of calcium carbonate in the water suspension obtained in this comparative example. From the measurement results of the particle size distribution, the calcium carbonate in the water suspension obtained in this Comparative Example has a dispersibility which is not good as compared with the dispersibility of the calcium carbonates of Examples 1, 2 and 3. It is confirmed that it is doing.
【００２４】比較例５ 比重１．０５５で温度が８℃の石灰乳７０００リッター
に、炭酸ガスを２４m3の流速で導通し炭酸化反応を行
い、pH１０．８（Ｘ）の炭酸カルシウムの水懸濁液を得
た。この炭酸カルシウムは、電子顕微鏡で観察した結
果、一次粒子径が０．０５μｍの炭酸カルシウムであっ
た。その後３０℃で１０分間放置し、炭酸カルシウム水
懸濁液の２５℃におけるpHが１１．００（Ｙ）に達した
時点でヌッチェを用いて濃縮し、次いで得られた濃縮し
た水懸濁液に再度水を加え攪拌し、脱水前の炭酸カルシ
ウム水懸濁液と同一濃度の炭酸カルシウム水懸濁液を得
た。該炭酸カルシウム水懸濁液のpHは１０．９６（Ｚ）
であった。本比較例で得られた水懸濁液中の炭酸カルシ
ウムの粒度分布測定結果を表２に示す。粒度分布の測定
結果から、本比較例で得られた水懸濁液中の炭酸カルシ
ウムは、実施例１、２、３の炭酸カルシウムの分散性と
比較し、良好とは言えない分散性を有していることが確
認される。Comparative Example 5 Carbon dioxide gas was passed through 7,000 liters of lime milk having a specific gravity of 1.055 and a temperature of 8 ° C. at a flow rate of 24 m 3 to carry out a carbonation reaction, and water suspension of calcium carbonate having a pH of 10.8 (X) was carried out. A suspension was obtained. As a result of observing with an electron microscope, this calcium carbonate was calcium carbonate having a primary particle diameter of 0.05 μm. Then, the mixture was left to stand at 30 ° C for 10 minutes, and when the pH of the calcium carbonate aqueous suspension at 25 ° C reached 11.00 (Y), it was concentrated using a Nutsche, and then the concentrated aqueous suspension obtained was obtained. Water was added again and the mixture was stirred to obtain a calcium carbonate aqueous suspension having the same concentration as the calcium carbonate aqueous suspension before dehydration. The pH of the calcium carbonate aqueous suspension is 10.96 (Z)
Met. Table 2 shows the particle size distribution measurement results of calcium carbonate in the water suspension obtained in this comparative example. From the measurement results of the particle size distribution, the calcium carbonate in the water suspension obtained in this Comparative Example has a dispersibility which is not good as compared with the dispersibility of the calcium carbonates of Examples 1, 2 and 3. It is confirmed that it is doing.
【００２５】比較例６ 比重１．０５５で温度が８℃の石灰乳７０００リッター
に、炭酸ガスを２４m3の流速で導通し炭酸化反応を行
い、２５℃におけるpH１０．１（Ｘ）の炭酸カルシウム
の水懸濁液を得た。該水懸濁液を５０℃で３６時間攪拌
し、２５℃におけるpHが１１．７の炭酸カルシウム水懸
濁液を得た。本比較例で得られた水懸濁液中の炭酸カル
シウムの粒度分布測定結果を表２に示す。粒度分布の測
定結果から、本比較例で得られた水懸濁液中の炭酸カル
シウムは、比較例中においては良好な結果をしめしてい
るものの、ほぼ同様の方法で調製した実施例２の炭酸カ
ルシウムの分散性と比較し、良好とは言えない分散性を
有していることが確認される。表１、表２中のＤ２５、
Ｄ５０、Ｄ７５は、粒度分布測定結果の粗粒子側から起
算した２５重量％、５０重量％、７５重量％の粒径を示
している。Comparative Example 6 Calcium carbonate having a pH of 10.1 (X) at 25 ° C. was introduced by introducing carbon dioxide gas into 7,000 liters of lime milk having a specific gravity of 1.055 and a temperature of 8 ° C. at a flow rate of 24 m 3. A water suspension of The aqueous suspension was stirred at 50 ° C for 36 hours to obtain an aqueous calcium carbonate suspension having a pH of 11.7 at 25 ° C. Table 2 shows the particle size distribution measurement results of calcium carbonate in the water suspension obtained in this comparative example. From the measurement result of the particle size distribution, although the calcium carbonate in the water suspension obtained in this Comparative Example showed a good result in Comparative Example, the carbonate of Example 2 prepared by substantially the same method. It is confirmed that the dispersibility is not so good as compared with the dispersibility of calcium. D25 in Table 1 and Table 2,
D50 and D75 represent the particle diameters of 25% by weight, 50% by weight, and 75% by weight calculated from the coarse particle side of the particle size distribution measurement result.
【００２６】[0026]
【表１】 [Table 1]
【００２７】[0027]
【表２】 [Table 2]
【００２８】応用例１ 実施例１、２、３及び比較例１、３、４、５、６で調製
された炭酸カルシウムの水懸濁液に、炭酸カルシウム固
形分に対し樹脂酸ソーダを３．０重量％表面処理した
後、フィルタープレスで脱水し、乾燥粉砕により各々炭
酸カルシウムの塗料用顔料粉体を得た。これら炭酸カル
シウム粉体４６重量部に短油アルキッド樹脂（商品名
「フタルキッド２３５」の２５％キシレン溶液）５４重
量部を加え、顔料容積濃度が６２％に調製し、さらにガ
ラスビーズを加えペイントシェーカーにより３０分間混
練させて、塗料ミルベースを作成した。ＪＩＳ Ｋ ５
４００による方法で、該ミルベースの粒の大きさを測定
し、各々の炭酸カルシウム粉体の分散性を比較した。測
定結果を表３に示す。表３の結果から、実施例の炭酸カ
ルシウム水懸濁液を原料として調製された顔料粉体は、
比較例の炭酸カルシウムと比較して、極めて良好な分散
性を有していることが確認される。Application Example 1 In an aqueous suspension of calcium carbonate prepared in Examples 1, 2, 3 and Comparative Examples 1, 3, 4, 5, and 6, sodium carbonate resin was added to the calcium carbonate solid content. After surface treatment of 0% by weight, the product was dehydrated with a filter press and dried and pulverized to obtain pigment powders for paints of calcium carbonate. To 46 parts by weight of these calcium carbonate powders, 54 parts by weight of a short oil alkyd resin (25% xylene solution of the brand name "Ptalkid 235") was added to adjust the pigment volume concentration to 62%, and glass beads were further added to it by a paint shaker. The mixture was kneaded for 30 minutes to prepare a paint mill base. JIS K 5
According to the method of 400, the size of the grains of the mill base was measured, and the dispersibility of each calcium carbonate powder was compared. The measurement results are shown in Table 3. From the results of Table 3, the pigment powders prepared by using the calcium carbonate aqueous suspension of Example as a raw material,
It is confirmed that it has extremely good dispersibility as compared with the calcium carbonate of the comparative example.
【００２９】[0029]
【表３】 [Table 3]
【００３０】応用例２ 実施例１、２、３及び比較例１、３、４、５、６で調製
された炭酸カルシウムの水懸濁液を乾燥粉砕し、各炭酸
カルシウム粉体を調製した。これら粉体各々の炭酸カル
シウム固形分１００重量部に対しＨＬＢが１６のショ糖
ステアリン酸エステルを２５重量部、及び水を混合し、
炭酸カルシウム固形分濃度が２０重量％の炭酸カルシウ
ム粉体の水懸濁液１５００ｇを調製し、超音波分散機Ｕ
Ｓ−３００Ｔ（日本精機製作所製）を用い、２０kHz 、
３００Ｗで１５分間超音波照射を行い、その後水で希釈
し炭酸カルシウム固形分濃度が５重量％のスラリー状牛
乳添加用炭酸カルシウムを調製した。これら炭酸カルシ
ウム固形分濃度が５重量％のスラリー状牛乳添加用炭酸
カルシウム各々８００ｇを、６０℃で溶解させたバター
５００ｇ中に分散させ、これを脱脂乳１０kg中に添加攪
拌し、次いで殺菌してカルシウム強化牛乳を得た。この
カルシウム強化牛乳を１００mlのメスシリンダーにと
り、５℃で保存し、定期的にメスシリンダー中の牛乳を
静かに廃棄し、メスシリンダー底部に残存している沈降
物の量の経時変化を目視観察した。その結果を下記の３
段階表示により表４に示す。 （沈澱の量） 殆ど確認できない ３ わずかに沈澱が確認できる ２ かなり大量の沈澱が確認できる １Application Example 2 The aqueous suspensions of calcium carbonate prepared in Examples 1, 2, 3 and Comparative Examples 1, 3, 4, 5, 6 were dried and pulverized to prepare each calcium carbonate powder. 25 parts by weight of sucrose stearate ester having an HLB of 16 and 100 parts by weight of calcium carbonate solid content of each of these powders and water are mixed,
1,500 g of an aqueous suspension of calcium carbonate powder having a calcium carbonate solid content concentration of 20% by weight was prepared.
Using S-300T (Nippon Seiki Seisakusho), 20kHz,
Ultrasonic irradiation was performed at 300 W for 15 minutes, and then diluted with water to prepare a slurry-form calcium carbonate for adding milk having a calcium carbonate solid content concentration of 5% by weight. 800 g of each calcium carbonate for adding milk slurry having a solid content of 5% by weight of calcium carbonate was dispersed in 500 g of butter dissolved at 60 ° C., added to 10 kg of skim milk, stirred, and then sterilized. Got calcium-fortified milk. This calcium-fortified milk was placed in a 100 ml graduated cylinder, stored at 5 ° C., the milk in the graduated cylinder was gently discarded, and the change with time in the amount of sediment remaining at the bottom of the graduated cylinder was visually observed. .. The result is shown in 3 below.
It is shown in Table 4 by the step display. (Amount of precipitation) Almost no precipitation 3 A slight precipitation 2 A fairly large quantity of precipitation 1
【００３１】表４の結果から、実施例の炭酸カルシウム
の水懸濁液を原料として調製された粉体は、分散性が良
好なため、同一条件で超音波分散して調製された比較例
の炭酸カルシウム粉体と比較し、牛乳中における分散安
定性が極めて優れており、その結果、本発明の方法で調
製した炭酸カルシウムを原料とした炭酸カルシウム粉体
を牛乳中に分散させることにより、長期間安定なカルシ
ウム強化牛乳が得られていることが確認できる。From the results shown in Table 4, since the powder prepared from the aqueous suspension of calcium carbonate of the example has a good dispersibility, the powder of the comparative example prepared by ultrasonic dispersion under the same conditions was prepared. Compared with the calcium carbonate powder, the dispersion stability in milk is extremely excellent. As a result, by dispersing the calcium carbonate powder prepared from the calcium carbonate prepared by the method of the present invention in milk, It can be confirmed that stable calcium-fortified milk was obtained for a period of time.
【００３２】[0032]
【表４】 [Table 4]
【００３３】[0033]
【発明の効果】叙上の通り、本発明によれば、二次凝集
が少なく、分散性の良好な合成炭酸カルシウムが提供さ
れる。As described above, according to the present invention, there is provided a synthetic calcium carbonate having less secondary aggregation and good dispersibility.
Claims (6)
て得られる炭酸カルシウムの水懸濁液の調製工程におい
て、炭酸化反応終了して調製されたpH値Ｘの炭酸カルシ
ウムの水懸濁液を攪拌、及び／又は湿式粉砕、及び／又
は静置し、該炭酸カルシウムの水懸濁液のpHを以下に示
す式（ａ）及び（ｂ）を満たすpH値Ｙに上昇せしめた
後、水懸濁液中に存在するアルカリ物質を除去及び／又
はアルカリ物質の単位体積当たりの濃度を低下せしめ、
炭酸カルシウムの水懸濁液のpHを、以下に示す式（ｃ）
を満たすpH値Ｚに調整することを特徴とする、炭酸カル
シウム分散体の製造方法。 Ｙ≧８．６ ・・・（ａ） １０(Y+2) ／１０X ≧１２５ ・・・（ｂ） １０(Z+2) ／１０Y ≦８０ ・・・（ｃ） 但し、Ｘ、Ｙは同一温度条件下でのpHである。pH値Ｚ
は、Ｚが８．６未満の場合、Ｚは８．６として計算。1. A water suspension of calcium carbonate having a pH value X prepared after completion of the carbonation reaction in the step of preparing an aqueous suspension of calcium carbonate obtained by carbonating lime milk with carbon dioxide gas. After stirring and / or wet pulverizing the suspension, and / or allowing it to stand still, the pH of the aqueous suspension of calcium carbonate is increased to a pH value Y satisfying the formulas (a) and (b) shown below. Removing alkaline substances present in a water suspension and / or reducing the concentration of alkaline substances per unit volume,
The pH of an aqueous suspension of calcium carbonate is calculated by the formula (c) shown below.
A method for producing a calcium carbonate dispersion, which comprises adjusting the pH value Z to satisfy the above condition. Y ≧ 8.6 (a) 10 (Y + 2) / 10 X ≧ 125 (b) 10 (Z + 2) / 10 Y ≦ 80 (c) where X and Y Is the pH under the same temperature conditions. pH value Z
When Z is less than 8.6, Z is calculated as 8.6.
水懸濁液に炭酸ガスを反応せしめ、炭酸カルシウムの水
懸濁液のpHをＺに調整する請求項１記載の製造方法。2. The method according to claim 1, wherein the pH of the calcium carbonate aqueous suspension is adjusted to Z by reacting carbon dioxide gas with the calcium carbonate aqueous suspension whose pH value is increased to Y.
水懸濁液に水を加え希釈し、炭酸カルシウムの水懸濁液
のpHをＺに調整する請求項１記載の製造方法。3. The method according to claim 1, wherein the pH of the calcium carbonate aqueous suspension is adjusted to Z by adding water to the calcium carbonate aqueous suspension whose pH value has been increased to Y, and diluting it.
水懸濁液を脱水し、得られる含水ケーキに水を加え希釈
し、炭酸カルシウムの水懸濁液のpHをＺに調整する請求
項１記載の製造方法。4. An aqueous suspension of calcium carbonate whose pH value has been raised to Y is dehydrated, water is added to the obtained water-containing cake to dilute it, and the pH of the aqueous suspension of calcium carbonate is adjusted to Z. 1. The manufacturing method according to 1.
１〜５．０μｍである請求項１記載の製造方法。5. The primary particle size of calcium carbonate is 0.0
The manufacturing method according to claim 1, which is 1 to 5.0 μm.
載の製造方法。6. The production method according to claim 1, wherein the pH value X is 11.0 or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15598992A JP3786717B2 (en) | 1992-05-22 | 1992-05-22 | Method for preparing calcium carbonate dispersion |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15598992A JP3786717B2 (en) | 1992-05-22 | 1992-05-22 | Method for preparing calcium carbonate dispersion |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05319815A true JPH05319815A (en) | 1993-12-03 |
| JP3786717B2 JP3786717B2 (en) | 2006-06-14 |
Family
ID=15617921
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15598992A Expired - Fee Related JP3786717B2 (en) | 1992-05-22 | 1992-05-22 | Method for preparing calcium carbonate dispersion |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3786717B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6592837B2 (en) * | 2001-04-20 | 2003-07-15 | Carbominerals | Narrow size distribution ground calcium carbonate compositions |
| JP2007528947A (en) * | 2003-07-15 | 2007-10-18 | ユーピーエム−キンメネ コーポレイション | Papermaking method and paper |
| WO2010142859A1 (en) | 2009-06-12 | 2010-12-16 | Nordkalk Oyj Abp | Method of producing calcium carbonate |
-
1992
- 1992-05-22 JP JP15598992A patent/JP3786717B2/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6592837B2 (en) * | 2001-04-20 | 2003-07-15 | Carbominerals | Narrow size distribution ground calcium carbonate compositions |
| JP2007528947A (en) * | 2003-07-15 | 2007-10-18 | ユーピーエム−キンメネ コーポレイション | Papermaking method and paper |
| JP4897481B2 (en) * | 2003-07-15 | 2012-03-14 | ユーピーエム−キンメネ コーポレイション | Papermaking method and paper |
| WO2010142859A1 (en) | 2009-06-12 | 2010-12-16 | Nordkalk Oyj Abp | Method of producing calcium carbonate |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3786717B2 (en) | 2006-06-14 |
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